RESUMO
Atmospheric aerosols have a tremendous influence on visibility, climate, and human health. New particle formation (NPF) is a crucial source of atmospheric aerosols. At present, certain field observations and experiments have discovered the presence of 3-hydroxy-4,4-dimethylglutaric acid (HDMGA), which may participate in NPF events. However, the nucleation mechanism of HDMGA has not been clearly understood. In addition, dimethylamine (DMA) is an important precursor of nucleation. The nucleation mechanism involving HDMGA and DMA has not been studied. In this study, the most stable structures of (HDMGA)(H2O)n (n = 0-3) and (HDMGA)(DMA)(H2O)n (n = 0-3) were obtained by using M06-2X coupled with the 6-311++G(3df,3pd) basis set. The α-carboxyl group is directly attached to the amino group in all the most stable configurations. Proton transfer enhances the strength of a hydrogen bond, as well as promotes the generation of a global minimum structure. Temperature has a considerable influence on the distribution of isomers for (HDMGA)(DMA)(H2O)3 as compared to the other investigated clusters. The Gibbs free energy values reveal that most of the clusters can exist in NPF, except for (HDMGA)(H2O)1. The process of adding a cluster of (H2O)n more likely occurs in the atmosphere than gradually adding a single water molecule.
RESUMO
Ammonia and amines are important common trace atmospheric species that can enhance new particle formation (NPF) in the Earth's atmosphere. However, the synergistic effect of these two bases involving nucleation is still lacking. We studied the most stable geometric structures and thermodynamics of quaternary (NH3)(CH3NH2)(H2SO4) m(H2O) n ( m = 1-3, n = 0-4) clusters at the PW91PW91/6-311++G(3df,3pd) level of theory for the first time. We find that the proton transfer from H2SO4 molecule to CH3NH2 molecule is easier than to NH3 molecule in the free or hydrated H2SO4-base clusters, and thus leads to the stability. The energetically favorable formation of the (NH3)(CH3NH2)(H2SO4) m(H2O) n ( n = 0-4) clusters, by hydration or attachment of base or substitution of ammonia by methylamine at 298.15 K, indicate that ammonia and methylamine together could enhance the stabilization of small binary clusters. At low RH and an ambient temperature of 298.15 K, the concentration of total hydrated (NH3)(CH3NH2)(H2SO4)2 clusters could reach that of total hydrated (NH3)(H2SO4)2 clusters, which is the most stable ammonia-containing cluster. These results indicate that the synergistic effect of NH3 and CH3NH2 might be important in forming the initial cluster with sulfuric acid and subsequently growth process. In addition, the evaporation rates of (NH3)(CH3NH2)(H2SO4)(H2O), (NH3)(CH3NH2)(H2SO4)2 and (NH3)(CH3NH2)(H2SO4)3 clusters, three relative abundant clusters in (NH3)(CH3NH2)(H2SO4) m(H2O) n system, were calculated. We find the stability increases with the increasing number of H2SO4 molecules.
RESUMO
Graves' disease (GD) is the most common cause of hyperthyroidism in the clinic, accounting for about 85% of all hyperthyroidisms. However, hyperthyroidism combined with OH has been rarely reported in the international community. We analyzed the clinical characteristics and pathogenesis of GD combined with orthostatic hypotension. We conducted a retrospective analysis of 2 GD combined with orthostatic hypotension cases diagnosed by Chinese and Western Medical Association Hospital of Southern Medical University from July to August 2018 and discussed their clinical characteristics, treatment methods, and pathogenesis. The main clinical manifestations of both two patients with hyperthyroidism were vertigo during postural changes or activities and relief from supine position and blood volume supplementation. Considering the lack of blood volume, the symptoms were alleviated after symptomatic treatment. The possibility of hyperthyroidism combined with orthostatic hypotension should be taken into consideration in clinical diagnosis and treatment.
Assuntos
Doença de Graves , Hipertireoidismo , Hipotensão Ortostática , Humanos , Estudos Retrospectivos , Hipotensão Ortostática/complicações , Doença de Graves/complicações , Doença de Graves/diagnóstico , Doença de Graves/tratamento farmacológicoRESUMO
OBJECTIVE: To compared the differentiation capacity of rat adipose-derived stem cells (ASCs) and bone marrow mesenchymal stem cells (BMSCs) into endothelial cells. METHODS: Rat BMSCs and ASCs were isolated, cultured and identified for cell surface markers using flow cytometry. The cell growth curves were drawn by CCK-8 assay, and the cells in active growth were induced for endothelial differentiation following standard protocols. On day 21 of induction, the cells were examined for mRNA expressions of endothelial cell specific markers CD31, KDR, and vWF using qPCR. Immunostaining was performed to observe the expression of CD31 on the cells. The induced cells were also tested for Dil-labeled acetylated low-density lipoprotein (ac-LDL) uptake ability. The tube-forming ability of the induced cells was verified on Matrigel. RESULTS: We successfully isolated rat ASCs and BMSCs. Morphologically, ASCs were similar with BMSCs, both having long spindle-shaped and fibroblast-like morphology. Flow cytometry showed that both BMSCs and ASCs had high expressions of mesenchymal markers CD29 and CD90 and a low expression of hematopoietic cell surface markers CD45. CCK-8 assay showed that ASCs proliferated more quickly than BMSCs. The cells with induced endothelial differentiation exhibited increased levels of CD31, KDR, and vWF mRNA expressions and immunofluorescent staining identified CD31 antigen expression on the cell membrane. Fluorescence microscopy revealed red fluorescence in the induced cells suggesting uptake of Dil-Ac-LDL by the cells. The induced cells were capable of forming tube on Matrigel, confirming their identity of endothelial cells. CONCLUSION: Both rat BMSCs and ASCs can be induced to differentiate into endothelial cells, but ASCs differentiate more quickly into endothelial cells and possess a stronger proliferation ability, suggesting its greater potential than BMSCs in future applications.
Assuntos
Tecido Adiposo/citologia , Diferenciação Celular , Células Endoteliais/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco/citologia , Animais , Células da Medula Óssea , Células Cultivadas , RatosRESUMO
Acyclovir (ACV) is an effective and widely used antiviral agent. However, its clinical application is limited by severe nephrotoxicity. We assessed ACV-induced nephrotoxicity and identified the differentially expressed proteins using mass spectrometry-based proteomic analysis. In total, 30 ICR mice were intraperitoneally administrated ACV (150 or 600 mg/kg per day) for 9 days. After administration of ACV, levels of serum creatinine and urea nitrogen increased significantly. In addition, mouse kidneys exhibited histopathological changes and reduced expression levels of vascular endothelial growth factor (VEGF) and its receptor VEGFR2. In the proteomic analysis, more than 1,000 proteins were separated by two-dimensional polyacrylamide gel electrophoresis, and a total of 20 proteins were up- or down-regulated in the ACV group compared with the saline group. Among these, six proteins (MHC class II antigen, glyoxalase 1, peroxiredoxin 1, αB-crystallin, fibroblast growth factor receptor 1-IIIb, and cytochrome c oxidase subunit Vb) were identified in association with ACV-induced nephrotoxicity. These findings were confirmed by Western blotting analysis. The differential expression levels of α-BC, Prx1, Glo I and CcO Vb suggest that oxidative damage and mitochondrial injury may be involved in ACV-induced nephrotoxicity. Furthermore, VEGF and FGF may play a role in tissue repair and the restoration process following ACV nephrotoxicity.
Assuntos
Aciclovir/toxicidade , Antivirais/toxicidade , Nefropatias/induzido quimicamente , Rim/efeitos dos fármacos , Rim/patologia , Proteoma/análise , Animais , Creatinina/sangue , Modelos Animais de Doenças , Rim/metabolismo , Rim/fisiopatologia , Nefropatias/sangue , Nefropatias/metabolismo , Nefropatias/patologia , Nefropatias/fisiopatologia , Testes de Função Renal , Camundongos , Camundongos Endogâmicos ICR , Proteoma/metabolismo , Proteômica , Fator A de Crescimento do Endotélio Vascular/análise , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análiseRESUMO
We report a case of hypereosinophilic syndrome in a 47-year-old man who had acute pneumothorax as the initial presentation. Peripheral blood eosinophil count increased continuously over a period of 1 month and was associated with pulmonary changes and appearance of skin lesions on the right chest wall. Idiopathic hypereosinophilic syndrome was confirmed by bone marrow aspiration biopsy and skin lesion biopsy after exclusion of all possible secondary etiologies. The clinical status and chest radiographs showed marked improvement after treatment with corticosteroids.
Assuntos
Pneumotórax/etiologia , Eosinofilia Pulmonar/complicações , Biópsia , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Pneumotórax/diagnóstico , Eosinofilia Pulmonar/diagnóstico , Radiografia Torácica , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: To evaluate the effect of short-term intensive therapy on blood glucose control, BETA-cell function, and blood lipid levels in newly diagnosed type 2 diabetic patients. METHODS: Out-patients with newly diagnosed type 2 diabetic patients were enrolled for intensive treatment with sulfonylureas and metformin for 12 weeks, and the therapeutic effect was evaluated. RESULTS: After the intensive treatment, FPG, 2 hPG, and HbA1c decreased significantly (P<0.01); HOMA-IR decreased and HOMA-B increased significantly (P<0.01), and TG, CHOL, LDL decreased significantly (P<0.01) after the treatment. CONCLUSION: Short-term intensive treatment with glimepiride combined with metformin is safe and effective in newly diagnosed type 2 diabetic patients with HbA1c>9%.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Metformina/uso terapêutico , Compostos de Sulfonilureia/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the quality of life (QOL) in patients with esophageal carcinoma after thoracoscopic and laparoscopic esophagectomy and circular stapled cervical esophagogastric anastomosis via retrosternal route or three-incision open surgery. METHODS: A total of 63 patients with middle-upper esophageal carcinoma who underwent radical surgical resection from January 2009 to October 2010 were enrolled in this study. Thirty-three patients underwent combined laparoscopic and thoracoscopic surgery and 30 three-incision open surgery. The EORTC questionnaire QLQ-C30 and QLQ-OES18 were used to evaluate the QOL. RESULTS: There were no significant differences in the clinical data between the two groups except for anastomosis method(P>0.05). In the endoscopy group, there was one patient developed anastomotic leakage(3.0%, 1/33), 1 postoperative wound infection in the neck (3.0%, 1/33), and 1 anastomotic stricture(3.0%, 1/33). In the open group, 8 patients had anastomotic leakage (26.7%, 8/30), 2 had anastomotic stricture (6.7%, 2/30), 1 had wound infection in the neck (3.3%, 1/30), and 6 had pulmonary infection (20.0%, 6/30). All the complications were managed by conservative treatment. The two groups differed in dysphagia, food intake, pain, obstruction, dyspnea, anorexia, fatigue, financial condition, physical function, role function, emotional function, cognitive function, social function and global health level and were more favorable in the endoscopy group(P<0.05), while there were no significant differences in the other dimensions. CONCLUSIONS: The postoperative complication rate is low after thoracoscopic and laparoscopic esophagectomy. Stapled anastomosis is associated with lower rate of anastomotic leak. QOL is better in patients following thoracoscopic and laparoscopic esophagectomy as compared to those following three-incision open surgery.
Assuntos
Anastomose Cirúrgica/métodos , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Qualidade de Vida , Idoso , Esôfago/cirurgia , Feminino , Seguimentos , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Estômago/cirurgia , ToracoscopiaRESUMO
OBJECTIVE: To evaluate the clinical value of sweat function examination in early diagnosis of diabetic peripheral neuropathy (DPN). METHODS: Ninety-eight hospitalized type 2 diabetic patients with or without DPN (DN and DC groups) according to Michigan Diabetic Neruopathy Score (DNS) and 40 healthy volunteers (NC group) were evaluated for their sweat function of the feet in relation to the peripheral autonomic nerve with sweat printing method using Neuropad. The Neuropad color-changing time was recorded to assess the sensitivity and specificity of sweat printing methods relative to DNS for DNP evaluation, and the correlation of the Neuropad color-changing time to DNS score was analyzed. RESULTS: The average Neuropad color-changing time was 4.0-/+0.6, 4.3-/+1.2 and 23.0-/+6.1 min in NC, DC, and DN groups, respectively, showing significant differences between the 3 groups (P<0.05). The morbidity rate detected by sweat printing method was 62.2%, similar to that detected by DNS (57.1%, P>0.05). The sensitivity of the sweat printing method for DPN diagnosis was 92.8%, with specificity of 78.5%, positive predictive value of 93.2%, and negative predictive value of 78.6%. DNS showed significant positive correlation with the Neuropad color-changing time (r=0.46, P<0.05). CONCLUSION: Sweat printing method provides an objective, simple and reliable method for sweat function evaluation of the feet of type 2 diabetic patients to help in early DPN diagnosis, and quantification of the results of sweat printing method can be indicative of the DPN severity.